Drop frontbuffers with ui-use-gpu-process, synchronized with browser, decoupled from backbuffer dro…

content/common/gpu/texture_image_transport_surface.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CONTENT_COMMON_GPU_TEXTURE_IMAGE_TRANSPORT_SURFACE_H_
 #define CONTENT_COMMON_GPU_TEXTURE_IMAGE_TRANSPORT_SURFACE_H_
 #pragma once
 
 #include "base/basictypes.h"
 #include "content/common/gpu/gpu_command_buffer_stub.h"
@@ skipping 30 matching lines @@
   virtual void* GetDisplay() OVERRIDE;
   virtual void* GetConfig() OVERRIDE;
 
  protected:
   // ImageTransportSurface implementation.
   virtual void OnNewSurfaceACK(
       uint64 surface_handle, TransportDIB::Handle shm_handle) OVERRIDE;
   virtual void OnBuffersSwappedACK() OVERRIDE;
   virtual void OnPostSubBufferACK() OVERRIDE;
   virtual void OnResizeViewACK() OVERRIDE;
+  virtual void OnSetFrontSurfaceIsProtected(bool is_protected,
+                                            uint32 visibility_state_id)
+                                                OVERRIDE;

[piman, 2012/06/12 20:59:48]

nit: you can write it as:
virtual void OnSetFrontSurfaceIsProtected(
    bool is_protected,
    uint32 visibility_state_id) OVERRIDE;

It's a more conventional style.

   virtual void OnResize(gfx::Size size) OVERRIDE;
 
   // GpuCommandBufferStub::DestructionObserver implementation.
   virtual void OnWillDestroyStub(GpuCommandBufferStub* stub) OVERRIDE;
 
  private:
   // A texture backing the front/back buffer in the parent stub.
   struct Texture {
     Texture();
     ~Texture();
 
     // The client-side id in the parent stub.
     uint32 client_id;
 
     // The currently allocated size.
     gfx::Size size;
 
     // Whether or not that texture has been sent to the client yet.
     bool sent_to_client;
 
     // The texture info in the parent stub.
     gpu::gles2::TextureManager::TextureInfo::Ref info;
   };
 
   virtual ~TextureImageTransportSurface();
   void CreateBackTexture(const gfx::Size& size);
-  void ReleaseBackTexture();
   void AttachBackTextureToFBO();
+  void ReleaseTexture(int id);
   void ReleaseParentStub();
+  void AdjustFrontBufferAllocation();
+  int front() const { return front_; }
   int back() const { return 1 - front_; }
 
   // The framebuffer that represents this surface (service id). Allocated lazily
   // in OnMakeCurrent.
   uint32 fbo_id_;
 
   // The front and back buffers.
   Texture textures_[2];
 
   gfx::Rect previous_damage_rect_;
 
   // Indicates which of the 2 above is the front buffer.
   int front_;
 
   // Whether or not the command buffer stub has been destroyed.
   bool stub_destroyed_;
 
   bool backbuffer_suggested_allocation_;
   bool frontbuffer_suggested_allocation_;
 
+  bool frontbuffer_is_protected_;
+  uint32 visibility_state_id_;
+
   scoped_ptr<ImageTransportHelper> helper_;
   gfx::GLSurfaceHandle handle_;
   GpuCommandBufferStub* parent_stub_;
 
   DISALLOW_COPY_AND_ASSIGN(TextureImageTransportSurface);
 };
 
 #endif  // CONTENT_COMMON_GPU_TEXTURE_IMAGE_TRANSPORT_SURFACE_H_